Throttle Body: Operation

Filtered air from the air cleaner enters the intake manifold through the throttle body. The intake manifold contains an air control passage controlled by an Idle Air Control (IAC) motor. The air control passage is used to supply air for idle conditions. A pintle valve is used to supply air for above idle conditions.

The throttle position sensor (TPS) is attached to the throttle body. The accelerator pedal cable is connected to the throttle body linkage arm.

A (factory adjusted) set screw is used to mechanically limit the position of the throttle body throttle plate. Never attempt to adjust the engine idle speed using this screw.  All idle speed functions are controlled by the PCM.